1. Field
The present invention relates generally to digital television and broadcast systems and, more specifically, to providing event notifications for digital television programs.
2. Description
The broadcasting industry is expanding into digital broadcast technologies that promise new features, higher resolution video and audio, and other technological enhancements. Digital television (DTV) broadcasting provides at least several advancements in broadcast content enhancement. One type of content enhancement is the addition of supplemental information to the regular broadcast transmission. Supplemental information can take many forms, such as Hypertext Markup Language (HMTL), meta-data, and other information carrying data structures. Enhanced or interactive television incorporates the supplemental information into the viewing experience through interactive displays, links to web pages on the Internet, and other features.
The Advanced Television Enhancement Forum (ATVEF) (www.atvef.org) is a cross-industry alliance of companies representing broadcast and cable networks, television transports, the consumer electronics industry, and the personal computer (PC) industry. ATVEF has defined protocols for HTML-based enhanced television, which allow content creators to deliver enhanced programming over all forms of transport (analog, digital, cable, Internet and satellite) to intelligent receivers. ATVEF has published the Enhanced Content Specification, version 1.1, revision 26, 1998-2000 (hereinafter referred to as the “ATVEF Specification”) to promote consistent methods for providing enhancements in both analog and digital broadcasting systems. The ATVEF Specification provides a standard for delivering interactive TV experiences that can be authored once using a variety of tools and deployed to a variety of TV, set top box, and PC-based receivers. The ATVEF Specification specifies content formats and delivery mechanisms for the transmission and processing of triggers, resources, announcements, and content that are associated with an enhanced TV transmission. Such enhancements are often suitable for use by a computer system (such as a PC), connected to the Internet or other network. For example, one type of supplemental information is a Universal Resource Locator (URL) to a TV network's web site where additional information relating to a TV program may be found. In one scenario for enhanced TV viewing, a viewer may watch a TV program and be notified of a related web site. The viewer may then obtain one or more web pages from the identified web site and display them either on the TV screen or on another display concurrently with viewing the TV program.
When viewers watch TV, it is common for the viewers to follow multiple programs on different channels concurrently. For example, a person might be watching a movie on one channel while periodically checking the score of a football game shown on another channel. In another example, a family watching a national news program on a cable channel might want to switch to a local channel when the local weather report is broadcast. Currently, picture in picture (PIP) technology allows viewers to monitor programs on two channels simultaneously by using two tuners, each tuner receiving one channel and displaying the received program on a selected area of the TV screen. However, there is no mechanism for notifying viewers of interesting program events happening on multiple channels when only one program is being displayed. Thus, the viewer must frequently switch back and forth between channels to monitor what is being shown on different channels. This unnecessarily interrupts viewing of the primary program currently being watched by the TV viewer.